Automatic railway crossing gate



oct. 24, 1933. y F1 KAHLER 1,932,075

AUTOMATIC RAILWAY CROSSING GATE N VEA/TOR ANK /IHLEE 0d. 24, l1.933. F KAHLER 1,932,075

AUTOMATIC RAILWAY CROSSING GATE Filed Sept. 9, 1929 4 Sheets-Sheet 2 Oct. 24,1933. F. KAHLER AUTOMATIC RAILWAY CROSSING GATE 4 Sheets-Sheet 3 Filed Sept. 9, 1929 AI'IIIIIA lhlllll I I lllll IIII In Ven of Fran/f Hah /er By f/Q A o megs oct. 24, 1933. F. KAHLER 1,932,075

AUTOMATIC RAILWAY CROSSING GATE l Filed sept. I9, 1929 4 sheets-sheet 4 [n ven for I Fran/r fah/er aan Ar-Es PATENT OFFICE 1,932,075 i AUTOMATIC RAILWAY CROSSING GATE Frank Kahler, Burbank, Calif. Application September 9, 1929. Serial No. 391,288 6 Claims. (Cl. 246-130) This invention relates to an automatic railway crossing gate system, and particularly pertains t0 a method and means for automatically opening and closing railway crossing gates as generally indicated in a United States patent issued to me on November 30, 1920, No. 1,424,913, entitled Automatic swinging closure control, and my co-pending application iiled March 10, 1927, Serial No. 174,345, entitled Gate systems, and my application entitled Railway crossing gate, Serial No. 391,287, filed concurrently herewith.

This invention relates particularly to an electric safety gate system for use at railway crossings, and which will automatically operate to swing a gate across the roadway in an obstructing and warning position at the approach of trains;

the device being so designed as to be controlled in its operation by approaching trains, without the necessity or the presence of a watchman or iiagman, at the railway crossing, and in a manner to insure that the gate will automatically close a predetermined interval before the train reaches the crossing, irrespective of whether or not the train is traveling at a high rate of speed or at a low rate of speed; the structure further embodying means for 'automatically opening the gate when the train has passed.

The invention contemplates the provision of gates normally held in their opened positions at opposite sides of a railway crossing, and adapted to be automatically released at the approach of a train to operate-by gravity to swing horizontally to a closed position; the structure being so designed as to allow a vehicle to collide with the gate without possibility of damage to the gate or its operating mechanism; the release mechanism of the gate being electrically controlled through circuits which are normally closed, and operate through the usual track circuits with which railway lines are equipped.

The invention is illustrated by way of example in the accompanying drawings, in which:-

Fig. 1 is a view showing the gate with which the present invention is concerned, indicating the operating pit in vertical section and elevation.

Fig. 2 is an enlarged view in vertical section showing the operating pit of the gate, and particularly disclosing the manner in which the fluid valves are controlled 'by an electric switch mechanism. c v

Fig. 3 is an enlarged view in fragmentary section and elevation, showing the gate swinging mechanism. f

Fig. 4 is a composite View in perspective show-- ing the various essential elements of the gate Vto move along a helical swinging mechanism as operated and disposed, one above the other in a position to be telescoped and assembled. y

Fig. 5 .is a fragmentary View in vertical section showing, the relief valve construction of the gate operating ram. l

Fig. 6 is an enlarged fragmentary view in vertical vsection showing the relief valve as seen on the line 6-6 of Fig. 5.

Fig. 7 is afragmentary view in vertical section, 65 showing a regulating valve structure.

Fig. 8 is a wiring diagram, showing the complete electric system for automatically controlling the gate, and the relation of this system to the various gate elements as well as the railway track.

Referring more particularly to the drawings, 10 indicates a vertical standard mounted upon a base 11. This standard is designed to brace and support the post 12 of a gate 13. The post 12 is fixed at its upper end with a bearing` 1li, which is secured to the standard. Its lower end is mounted upon an inner operating cylinder 15, which is in vertical alignment therewith, and which carries an operating roller 16.` A flange 17 is formed at the upper end of the cylinder 15, and receives a bell shaft canopy 18, which normally conceals and protects the gate operating mechanism.

The roller 16 extends into a cam groove 19, formed in the side wall of an intermediate cam sleeve 20, into which the cylinder 15 telescopes. The cam groove is cast integral with the side wall of the sleeve 20, and extends circumferentially therearound for substantially one-quarter of the circumference of the sleeve, and then extends vertically along the path parallel to the axis of the sleeve.v The circumferentially extending portion is also helical. The cam sleeve 20 is also provided with a radially extending pin 21, carrying a roller 22. The pin 21 extends outwardly from the side wall, and its axis is in longitudinal alignment with the termination of the cam groove 16, previously described as being formed at the opposite end of the sleeve 20.

The roller 22 on the cam sleeve 20 is designed cam groove 23, formed in the side wall of an outer cam sleeve 24. The groove 23 extends circumferentially of the outer sleeve 24 for substantially one-quarter of the circumference of the sleeve and then extends vertically and in longitudinal alignment with the axis of the sleeve.

The outer cam sleeve 24 is provided with a circumscribing bolting ange 25 by which it is secured to a base plate 26 by bolts 27. The base with an inlet passage 42.

plate 26 forms the cover of an operating pit 28, which is disposed below the level of the ground and carries the mechanism by which the intermediate cam sleeve 20 is operated. The operating mechanism includes a fluid ram 29; a suitable source of fiuid under pressure 30, and a storage tank 31, from which the fluid may be delivered to the ram. The construction of the ram is particularly shown in Fig. 2v of the drawings, where it will'be seen to comprise a cylinder 32 with its longitudinal axis in vertical alignment with and beneath the longitudinal axis of the gate post 12. The lower end of the cylinder is closed by a cylinder headl 33, and the upper end of the cylinder is closed by a removable head 34.

A piston rod 35 extends through a stuffing box 36 in the removable head 34, and is fastened to the intermediate sleeve 20 of the gate operating mechanism' so that when piston 37moves upwardly, it will move the intermediate sleeve 20 in unison therewith. The piston 37 which is secured at the lower end of the piston rod 35, is mounted to reciprocate within the cylinder 32, and to operate under fluid pressure; the fluid being delivered to the lower end of the cylinder 32 through a duct 38, which extends into a fitting 39, the details of which are more particularly shown in Fig. 7 of the drawings. This fitting is formed with a chamber 40, with which the duct connects. An inlet port 41 is formed in the lower end of this chamber, and communicates A ballcheck 43 is positioned within the chamber 40 and is adapted to rest on an inclined floor at the bottom of the chamber 40, thus normally acting to close the passageway 41.

A by-pass duct 44 extends from the inlet 42 to a needle valve 'housing 45, which communicates with the chamber 40 through a passageway 46, .regulated by needle valve 47. This valve is threaded and extend'sinto a threaded bore 48.v

It will thus be seen that the volume and resulting pressure of the incoming fluid delivered to the cylinder 32 may be accurately regulated.

The passageway 42 of the fitting 39 is in communication with a T-fitting 49, connected by a pipe 50 with a two-way valve 5l. This valve has a supply pipe 52 leading to the fluid storage tank 31, and has an outlet 53 connected with the pipe 50. An exhaust outlet 54 is also formed as part of the valve and permits the air to exhaust from the cylinder 32, and the pipe 50when the fluid pressure is cut olf. The T 49 connectswith the conduit 55, which is in communicationf with a fitting 56. This`tting is secured -to the side wall of the cylinder 32 at a point above that of the fitting 39, and is in communication'with a duct 57, extending through the side wall at a point where it will be uncovered by the piston 37 when the piston is moved to its uppermost position. A ball check valve 58 is mounted in the tting and is normally held down upon its seat by a spring 59. It will, however, rise under extreme pressure in the Cylinder and will prevent excessive pressure within the cylinder while insuring that the cylinder is maintained in its elevated position at all times when the uid pressure is delivered to the ram.

In View of the fact that the upper end of the cylinder 32 is closed, it is evident that it Will be necessary for the air entrapped'therein to escape as the piston moves to its upper position, and to gradually move in to ll the void as the piston moves to its lower position. In order to control the movement of the piston at such times,

an escape duct 60 extends upwardly through the cylinder head 34 and into a, valve chamber 61. A ball valve 62 normally closes this duct, and a plug 63 is provided to seal the upper end of the valve chamber. A separate by-pass 'duct 64 is also formed in the cylinder head 34 and communicates with a needle valve passageway 65 which carries a needle valve 66. An outlet duct 66 also communicates with this passageway. By this -arrangement vthe Volume of air returning into the cylinder as the piston settles, may be controlled and thus the rate of travel of the piston accurately determined.

The fluid valve 51 is indirectly operated through a circuit which will hereinafter be described, by a solenoid 67. This solenoid is formed with two windings; a low resistance yvinding for initial operation of the valve, and a high resistance winding to holdv the valve in its normal condition when the ram is holding the gate closing mechanism in its uppermost position and holding the gate open. Y

The'solenoid 67 includes a plunger 68 which ex tends downwardly and is connected to a swinging arm 69 by a link 70. The link 70 is secured to this swinging arm and is fastened to a valve lever l'72 by which the valve 5l is directly operated. The low tension portion of the solenoid 67 is connected with conduits 74 and 75; one of which is connected in the wiring circuits, as will be hereinafter described, and the other of which leads to a contact nger 76, within a switch box 77, shown in Fig. 2 of the drawings. This contact finger normally contacts with a finger 78, connected with a conduit 79. A lift rod reciprocates vertically within the switch box and is lifted when the arm 69 is raised sufficiently. As this rod moves upwardly, it will encounter the free end of the member 78 and movecontact 81 into engagement with a xed Contact 82 to which the return Wire 83, of the high voltage solenoid winding is connected.

The general construction of the gate 13 may be varied to suit different conditions, the details of this construction, however, are more specifically set'forth in my co-pending application led concurrently herewith and entitled Railway crossing gate.

While the preferred form of gate structure is shown in the. drawings, and has been described in the foregoing portion of .the specification, it is to be understood that this invention is more particularly concerned with the manner of controlling said gate and causing it to automatically operate upon the approach and departure of a train, with relation to a particular crossing; the control system being so designed as to permit switch trains to operate along the trackway at each side of the crossing and to move in close proximity to the crossing without causing the gate to swing to a closed position; the arrangement further insuring that trains moving at a fast rate of speed and those moving at a slow rate of speed to cross the crossing, will act to cause the gate to close at substantially the same interval before the train reaches 4the crossing. This insures that when a slow ltrain approaches` it is not necessary to delay trafiic an unreasonable length ofl time as the trainA approaches the crossing, and also insures that when an approaching train is moving at a high rate of speed the gateswill close suiciently in advance of the arrival ofthe train vat the crossing to serve as a sufficient warning to the drivers of approaching vehicles, so that they may bring their vehicles to a stop before reaching the gate and moving onto the track.

The wiring diagram is shown in detailin Fig. 8 of the drawings, where 84 and 85 indicate the parallel rails of a railway track. This track is shown. as divided into the usual signal blocks, indicated as blocks A, B, and C. The block A is connected with a source of electrical energy 86 by a lead wire 87, securing one pole with rail 84, and lead wire 88 securing the opposite pole with the rail 85. The block 8 is provided with a source.

of electric energy 89 connected to rail 84 by wire 90, and to rail by wire 91. The block C is provided with a source of electric energy 92 connected with the rail 84 by a wire 93, and connected with the `rail 85 by Wire 94. Thisl is the usual method of supplying electrical energy to the individual blocks of a railway track, it being understood that the joints'95 between the contiguous ends of the rails upon opposite sides of ablock division are formed of insulating material to confine each electric circuit to the signal block and length of track included therein.

A signal relay 96 is connected to rails 85 and 84 of the track of block A by wires 97 and 98, respectively. A signal relay '99 is connected to the rails of the track of signal block B by wires 100 and 101, respectively. A signal relay 102l is connected to the rails of the track in signal block C by wires 103 and 104, respectively.

The armature 105 of relay 96 actuates a switch blade 106 which is connected withla conductor 107, leading to one side of a battery 108. The opposite side of this battery is connected by a conductor g 109 with the relay 110 of a time switch 111, which relay circuit may be completed through a conductor 112 to the switch blade 106, when the relay 96 is de-energized. The conductor 107 from battery 108 connects with switch blade 113 of the relay 99 in the signal block B. This switch blade is-normally in electrical contact with a wire 114 leading to one side of a coil 115 of a delay time relay 116. The opposite side of this coil connects with conductor 109, and it will thus be seen that when the switch 113 is closed, the coil 115 is normally energized. `This coil partially establishes a circuit from conductor 114 through conductor 117, along the switch blade-119 of the delay time relay 116. The switch blade connects with a wire 119 leading to a contact 120 of the time relay 110.

A switch blade 121 of the time relay connects with wire 107 through conductor 122. The armature blade 123 of the time relay 110 is designed to establish contact between wire 112 and a wire 124, leading to the normally opened contact point 125 of the signal relay 99, in signal block B. The delay time relay 116 is provided with a switch blade 126 moving in unison with the armature switch blade 119, and which normally establishes contact with a battery lead wire 127, leading to a battery 128. The oppositel pole of this battery connects with a gate control magnet 129, by wire 130, which is secured to one pole of the relay magnet v129. The opposite pole of this relay magnet is provided with a wire 131, leading to one side of the switch blade 132 ofthe signal relay magnet 102 of signal block C. This switch blade no1- mally establishes electrical connection with a wire 133, which leads to the switch blade 126 of the delay time relay 116.

am @D gates producing signals both audible and visible, and for recording the performance of the gates ,when they are operated bythe mechanism and when they are operated accidentally by being struck and swung from their obstructing position across the crossing. The gate control relay 129 is provided with an armature switch 134 which normally closes a circuit from a wire 135 to wire 136. The wire 135 is a lead wire from a source of electric supply 137. The wire 136 connects with the coil of a repeat relay 138 which is normally in closed circuit. The opposite side of the coil 1,38 connects vwith a wire 139, leading to the source of electric energy 137, through a suitable bus box. The individual bus bars and wires completing the circuit will not be separately described or assigned numerals.' v

Switch blade 140 of the repeat relay 138 is connected with a common lead wire 135, and is normally out of Contact with a conductor 141 leading to the iiasher relay 142. The coils of the flasher relay act upon an alternating switch blade 143 to alternately establish contact through conductor 144 and 145. The oscillating switch member 143 isconnected with a wire 146, secured to the lead wire 139, by which a circuit through the battery 137 may be completed. The oscillation of the switch armature 143 causes simultaneous corresponding movement of asher switches 147 and 148.

The conductor 149 connects with one side oi a source of electric supply 150. The opposite side of this source of supply connects with a Wire 151. This wire is a commonsupply wire which in the bus box connects with wires 152 and 153, leading to the-two separate gate units, and having identical functions as will be hereinafter described. v

The switch 147 to which the wire 149 connects is provided With two contacts adapted to be alternately engaged by the switch. One of these contacts connects -With a wire 154, which leads to one side of a signal light 158; the other circuit being completed along return wire 152.

The other contact of the switch 147 connects with a conductor 159 leading to one side of signal light 160, on the other gate unit, the circuitv being completed along return wire 153. Thus, alternate contact of the oscillating switch blade 147 will alternately establish circuits through the signal lights 1,58 and160 of the two gates.

The oscillating switch 148 is provided to alteryThe swinging blade is connected with a wire having wires 166 and 167 connected therewith for blinker lights 168 and 169. These lights are provided with a common lead wire 170, leading through a pivoted switch blade 171 carried by the gate and being completed throughv switch segment 172 to a wire 173. The wire 173 connects with wire 135, thus completing a circuit through the source of electric supply 137.

When the switch blade 148 oscillates so that contact is not made with the conductor 162, contact will be made with `a conductor 174, which leads to the bus box to switch segment 175 mounted upon the gate opposite from the one previously described. A pivoted switch 176 is designed to have delayed contact with the segment 175. This switch arm is connected with a wire 177 having wires 178 and 179 attached thereto and leading to blinker lights 180 and 181. A lead `wire 182 leads to the pivoted blade 183, adapted to contact with the segment 184. A wire 185 connects with this segment and is led through the bus box to complete a circuit along wire 135 to the source of energy 137.

The period of oscillation ofthe switches 147 and 148 will be determined by a time relay 186, which connectsthrough a wire 187 with one side of the source of electric energy 150. The other side of the relay connects with a wire 188, leading to a contact 189 of a switch blade 190, which moves in unison with the armature 140 of the repeat relay 138. The opposite sides of the blade 190 connect with the source of electric energy through wire 149. The blade 190, when in its lower position contacts with a wire 191, leading to the bus box where it connects with wires 192 and 193, respectively. One of these wires is attached to the signal bell 194 and the other wire is attached to the signal bell 195, the return circuit being completed through wires 153 and 152,

respectively.

In the operation of the time relay switch 186, gate switches '196 and 197 are operated. These switches are connected with the source of electric energy 150, through a wire 198. The switch 196 connects with operating solenoid 67 by a conductor 199, of one of the gates. The switch 197 connects with the operating solenoid 67 of the other of said gates, through a conductor 200. The circuits are completed by connecting the solenoids by wires 201 and 202 with lead wires 152 and 153, respectively.

A time recording mechanism is provided which normally indicates the time at which the gates are operatedand the interval during which they are held in their closed positions, but also indicates the times and intervals at vwhich the gates are struck, as in the case of collision when the gates are in a closed and signalling position.

In operation of the present invention, the performance of the train signal relay mechanism will be described as it will take place at the approach of a swiftly moving train, a slowly moving train, and a switch train which moves back and forth at one side of the crossing and nally proceeds along the track across the crossing, and in each of which events the apparatus is lntended to break the circuit through relay 129 in direct relation to the speed of the approaching train, and at the same time to insure that the gates will be operated to close a pre-determined period of time prior to the moment at which the train crosses the crossing. This will insure that when a slowly moving train approaches, vehicular trafic will not be unnecessarily delayed, and that when a swiftly moving train approaches, adequate warning will be given to cause the vehicles to come to a stop before moving onto the track.

When a train approaches at a fast rate of speed and enters block A, it will immediately complete a circuit through the wheels and axle of the train, from the rails 84 and 85, and will shut out the electric energy from the battery 86. This will cause the normally closed signal relay 96 to be de-energized, resulting in the simultaneous drop of its armature 105 and its switch blade 106. When this takes place, contact will be made from the switch blade 106 to conductor 112, so that a circuit will be completed from the battery 108 along conductor 107 to switch blade 106, thence along conductor 112 through the coil 110 of the delay relay, thence returning along conductor 109 to the opposite side of the battery 108. It is to be understood that the delay relay 110 is of such a construction as to cause the armature 123 to move slowly toward the coil 110 and to delay closing of the circuit through the armature 123.

It is intended that the period of operation of the delay relay 110 is so set as to insure that contact is made between conductor 112 and the armature 123 at an interval of time slightly greater than the minimum time required for a fast train to pass through signal block A, thus assuring that at a minimum speed set for fast train operation, the delay relay switch will not close before the fast train has entered block B. It will be understood that prior to the entry of the train into block B of the track, the signal relay 99 will be energized, and will hold its armature 113 upwardly to close a circuit along wire 107, through the armature blade 113 and thence along wire 114 through delay time relay 116. The circuit then being completed to the battery along conductor 109. This relay is in a normally closed circuit and holds its armature in contact with the wire 117 so that when the delay relay 110 closed prior to the entry of the train into block section B from section A, and the switch blade 121 makes contact at 120 with conductor 119, the delay time relay 116 will remain energized due lto the fact that the circuit through the switch blade 121 of the delay time relay 110 will be completed from the battery 108, along conductor 107 to conductor 122, thence switch blade 121 of the delay relay 110, thence along conductor 119 to armature blade 118 of the delay relay 116, and thence through the coil 115 of the delay relay to conductor 109, returning to the opposite side of the battery 108. In that event the circuits leading directly to the relay 129 will remain undisturbed and that relay will continue to be energized so that all of the gate and signal operating mechanism will remain inactive. If, however, the train reaches the block section B in a shorter length of time than the interval required to close the delay relay 110, and complete the circuit lthrough relay coil 115, just described, the train will shunt the circuit from the block battery 89 and through the signal relay 99, so that the armature blade 113 of the relay 99 will drop. This will break the circuit from thebattery 108 through conductor 117 and conductor 114 to the delay time relay 116, and thence through the coil 115 thereof, along conductor 109 to the battery, and will cause the delay time relay to be deenergized, whereby the circuit controlled by switch blade 126 from battery 128 along conductor 127 and thence from the switch blade along conductor 131 to the relay 129, will de-energize the coil of relay 129 and set the gate and signal mechanism in operation. The operation will not take place, however, until after a certain period of delay determined by the action of the delay time relay 116 in swinging its armature 118 downwardly, as well as its switch blade 126. After the train has passed out of track section block A, the battery 86 will again energize the relay 96 and this will lift the armature 105 and the switch blade 106 breaking the contact through the conductor 107 and the conductor 112 and through the coil 111 and the delay relay 110. In order to maintain this coil. energized, the required interval after the train has passed out or the block A, and the track relay 99 has become cle-energized by the presence of the train in block B, the delay relay 110 is thrown in circuit with conductor 107, through the switch blade ,113, to conductor 124 and thence through the armature blade 123 along conductor 112 through the coil 111 and returning along `wire 109.

In the event that the trainv is switching it may movev down the track through blocks A and B, and will not cause the gate magnet 129 to operate until such time as it might enter block C. Upon entering block C, the circuit through the magnet 129 will be broken by theblock signal relay 102, regardless of what may have transpired in the previous blocks, so that a slowly moving train will always actuate the gates upon entering blook C; so that a swiftly moving train will actuate the gates through the mechanism previously described a minimum interval prior to the time for the train to reach the crossing, and at substantially the same interval, a slow train would reach the crossing after it has entered the block C.

It will be assumed that the gates 13 are positioned as indicated diagrammatically in Fig. 8

of the drawings, and that their operating con-A structionv substantially as shown in Figs. 2 to 6, inclusive, in which event the gates are normally held in an opened position and at right angles to the railroad track, and upon release act by gravity to swing to obstructing positions transversely of the roadway 203, as indicated in the diagram in Fig. 8. When the approaching train has disturbed the various closed circuits of the block signal track sections A, B and C, in a manner to cause the gate control magnet relay 129 to become de-energized, the operating solenoids 67 of the two gates will be actuated to permit` the fluid underpressure within the ram 29 and beneath the piston 32 to escape through the eX- haust opening in the valve 51, wherebythe piston rod 35 will move downwardly in the direction of the arrow a, as indicated in Fig. 2 of the drawings, and will permit the intermediate sleeve 20 to move downwardly within the xed outer cam sleeve 24, and will cause the roller 22 to move downwardly along the cam groove 23 formed integral with the outer cam sleeve 24. This will cause the entire gate mechanism to move down-l wardly a vertical distance equal to the vertical movement of the roller 22 in the groove 23, and will cause the entire gate Ato swing horizontally a distance through an aro of substantially 90 degrees.

The release of the solenoids 67 was brought about due to their de-energization and the breaking of electric circuits through the switch members 196 and 197, which were connected with a conductor 198, leading to one side of a source of electrical energy 150. The circuit was then completed along a wire 151 to conductor 201 of one solenoid 67, .and conductor 202 of the other solenoid 67, and thence returning along conductors 199 and through the switches 196 and 197. At the same time that the solenoid switches 196 and 197 are` actuated, to break the circuits through solenoids 67, it is to be understood that the switches controlling the signal bells 194 and 195, the signal lights 158 and 160, and the blinker lights 168 and 169 and 180 and 181, will all be actuated through the circuits which have been previously described in detail, thus producing visible and audible warning that the gates are being closed and that the arrival of an approaching train is imminent. After the train has passed through the block section C all of the block signal relay units will be restored to their original positions, and all of the signal relays will be in closed circuits, whereby the entire block signal will be in condition for further operation.

It is intended that vthe gates shall remain closed for a pre-determined period after the departure of the train and for that reason the delay action relay 186 is provided. This relay delays the time at which the switches 196 and 197 will close. At the time the switches 196 and 197 close, the cores 68 of said switches will be drawn upwardly to estalbish communication from a source of Iiuid under pressure through pipes 52 and 50, to the bottom of the ram 26, which will tend to elevate the piston 32 and. which movement will be accompanied by a raising of the cam sleeve 20 within the outer cam 24, resulting in a rotation of the cam sleeve 20 as it raises.

As previously explained, the coils of the solenoids 67 are made in two windings; the iirst being a winding adapted to produce a heavy magnetic field, and to lift the cores or plungers 68 with considerable force. The circuit for these windings normally continues through the switches shown in Fig. 2 of the drawings, and from the lower contact 76 to the main blade 78 of the switch. As the plunger 68 is lifted, however, the lift rod 80 will break this contact and will establish an electric circuit through the switch nger 81 to `the contact 82 and the conductor 83, thus throwing the lighter wound winding of the solenoid into circuit and causing this to be maintained in circuit to hold the plunger in its elevated position at all times when the gate is not in operation. vAt'such times the gates will be in positions indicated by solid lines in Fig. 8 of the drawings.

The mechanism for opening and closing the gates as shown in Figs. 1 to 7, inclusive, is designed to permit the gates to be positively opened and to automatically close in the event that the actuating mechanism becomes inoperative. It

is also contemplated that in the event the gate is struck by an approaching vehicle whenthe gate is in its closed position, the gate will momentarily yield and swing away from .the striking object to thereafter swing back to its obstructing position when the object is backed away from the gate.

The manner in which the gate mechanism is operated may be understood by reference to Fig. 2 of the drawings and the following description. In Fig. 2 ofthe drawings the conductors leading to the solenoid 67 are indicated as 75 and 79. These terminal connections aresecured to wires 199 and 201, as shown in the wiring diagram in Fig. 8, and also to 200 and 202 as shown in the same diagram in which two sets of wires control duplicate gate operating mechanisms.

When the circuit has been suitably established' through the signal system as disclosed in wiring diagram Fig. 8, the solenoid 67 will be energized through the conductor 79 thence through the finger 78 to the -iinger 76 and thence through a conductor 74 through a portion of the solenoid coil completing the circuit through the conductor 75. This energization of the solenoid 67 will cause the plunger 68 to be raised which will pull upwardly upon the arm 69 through the links 70 and 71, and will swing the valve lever 72 to open the two-way valve 51. Fluid under pressure will then flow from the tank 31 through pipe 50 to the fitting 39 and will then flow through the conduit 38 into the bottom of the cylinder 32 of the ram 29. This will cause the piston 37 to move upwardly at a speed of travel controlled by the needle valve 66 in the relief valve which is disposed at the upper end of the'cylinder 32. As the piston moves upwardly it will force the telescoping sleeves 15 and 20 to move with relation to each other and will at the same time cause rotation of the sleeves to produce like rotation of the post 12 and thus cause the gate to swing to a signalling position. The piston rod 35 bears directly against the lower face of the cam sleeve 20, and its pins 21 will move in the fixed cam groove 23 to cause this sleeve to rotate as it is forced upwardly. This in turn will also cause the sleeve 15 to rotate due to the engagement 'if the pin 16 with the cam groove 19. When the piston 3 7 reaches the upper end of its stroke the iluid will create a back pressure through the check valve 58 to relieve the pressure and to prevent it from building up within the cylinder, since it can then compensate through the pipe 55. As the plunger 68 of the solenoid reaches its upper position the arm 69 will strike the lever pin 80 and cause the ringer 78 to break the contact with finger 76 and to establish contact between the contactors 81 and 82 which will establish a current through the portion of the solenoid connected with the conductors and 83 so that the solenoid will maintain a sustained load. When the circuits of the signal system are broken the sustaining circuit through the conductors 75 and 79 and 83 will be broken and will permit the operating mechanism of the gate to act by gravity to return to its original position, and the iiuid in the cylinder. to be forced outwardly through the iitting 39.

It will thus be seen that the device here disclosed provides positive automatic means for visually and audibly creating warnings at grade crossings prior to the approach of a train, and to interpose a barrier across the roadway which will tend to warn and prevent vehicle drivers from attempting to cross the railroad track, said apparatus embodying means for controlling the operation of the gate and signal mechanism irrespective of the speed of travel of the approaching train, and to insure that the gate will close at substantially the same period of time after the train has passed into a given signal block, regardless of the speed at which the train is traveling.

While I have shown the preferred form of my invention as now known to me, it will be understood that various changes may be made in combination, construction, and arrangement of parts by those skilled in the art without departing from the spirit of my invention as claimed.

Having thus described my invention, what I claim and desire to secure by Letters Patent is: 1. In combination with a railway track and a highway thereacross, a signal gate disposed adjacent to the intersection thereof and normally held in a non-obstructing position with relation to the highway, means normally holding Said gate in its non-obstructing position, means'adapted to actuate the gate to move it to its obstructing position, and means whereby a rapidly approaching train will cause the gate to swing to its obstructing position at a remote point from the crossing, and a slowly moving train. will, cause the gate to be operated at a point proximate the crossing whereby the gate will. be in its obstructing position for a substantially equal period of time prior to the arrival of the train, irrespective of its speed of approach.

2. In combination with a railway track and a lhighway thereacross, and signal gates normally disposed adjacent to the inter-section thereof, means normally holding said gates in a nonobstructing relation to the highway, means for positively moving said gates to an obstructing position with relation to the highway, electrical means disposed along the track at a point relatively remote to the crossing whereby to initiate said movement of the gate to its obstructing position after a pre-determined period of time, an intermediate electrical actuating means operable to sustain the circuit of the rst operating means in the event that said intermediate means is reached by the train within a pre-determined period after it has reached the first operating means, an'd to render the circuit of the the first operating means inoperative in the event that a longer period of time is required.

3. In combination with a railway track divided into block signal sections, and which track is crossed by a highway, a signal gate disposed adjacent to the intersection of the track and highway, means normally holding said gate in a nonobstructing position with relation to the highway, means positively swinging the gate to its obstructing position with relation to the highway; electric relay mechanism, controlled by the presence of a train in a signal block remote from the crossing whereby to initiate operation of the vgate to swing it to its obstructing position, an

electric relay in an intermediate signal block,

adapted to maintain said initiatively operated circuit in the event the train reaches said intermediate track section in a pre-determined period vof time and to temporarily interrupt and reestablish said initiatively established circuit in the event that the train reaches said intermediate track section after a pre-determined period of time.

4. An automatic crossing gate adapted to guard the highway at its intersection with the railway track, which includes a gate normally disposed in a non-obstructing position with relation to the highway, means acting directly to cause the gate to assume an obstructing and warning position. across the highway, electrical means at a point remote from the gate by which actuation of said gate operating means may be initiated when a train reaches said point, and means along the trackway intermediate said gate operating means, and said remote point, adapted to nullify the action of said remote operating means and to subsequently initiate the actuation of said gate operating means in the event that the train does not travel from the remote point to the intermediate point in a pre-determined period of time.

5. An automatic crossing gate adapted to guard gate to assume an obstructing and warning position across the highway, electrical means at a point remote from the gate by which actuation 0f said gate operating means may be initiated when a train reaches said point, and means along the trackway intermediate said gate operating means, and said remote point, adapted to nullify the action of said remote operating means and to subsequently initiate Ithe actuation of said gate operating means in the event that the train does not travel from the remote point to the interme- 15() initiating operation of the gate operating mechanism after a pre-determined period of time, means included in the intermediate relay for nullifying the action of the remote relay in the event that the train does not pass from the remote block to the intermediate block in a pre-determined period of time, and means in the intermediate block whereby operation of the gate mechanism is then initiated.

FRANK KAHLER. 

